1. Field of the Invention
The present invention relates to television receivers, and more particularly, to a method of performing a time-shift function and a television receiver using the same.
2. Discussion of the Related Art
A contemporary television receiver provides a function for pausing a displayed video signal. For example, while a broadcast signal of one channel is being received and a corresponding video signal is being viewed, the display of the video signal may be paused. It should be noted, however, that the reception of the broadcast signal proceeds in real time. Therefore, unless the television receiver is provided with a video signal storage medium, there will be at least some portion of the received signal lost to the viewer. The lost portion is equal in size to the duration of the pause operation and corresponds to the incoming signal stream received from the time of initiating the pause operation to the point of resuming real-time viewing of a currently received broadcast signal. In other words, upon resumption of the signal that was paused, the viewer will have missed some segment of the broadcast signal, since reception of the real-time-received broadcast signal naturally continued (without viewing) during the pause operation.
To overcome this problem, a television receiver may be provided with a storage medium, such as a hard disc, for storing in real time a video signal broadcast on one channel. To view the stored video content, the display of the real-time broadcast signal is discontinued to enable viewing of a display of the time-shifted content, which is reproduced using audio and video data stored on the hard disc. Typically, such a television receiver provides a display function utilizing an auxiliary area of the screen, e.g., a PIP screen, to enable a viewing of time-shifted content of a received broadcast signal, while a viewing of real-time content continues on the main screen area. Therefore, this television receiver displays a real-time broadcast program, stores the broadcast program being displayed, and reproduces the stored broadcast program, and by enabling the reproduced program to be viewed beginning from some previous point in time, a time-shift function is enabled.
The time-shift function of the above-described contemporary television receiver, however, is applicable to the broadcast program of a currently viewed channel only. That is, if the television receiver is tuned to another (new) channel, i.e., any broadcast or input channel other than a currently viewed channel, there is no existing data storage (prior recording) of the content of the new channel. Thereafter, if a user wishes to view content of the new channel, which is now the currently viewed channel, the time-shift function is ineffectual since there has been no recording of the new broadcast program prior to the point of changing the channel. In other words, any utilization of a time-shift function requires the recording of a video signal (e.g., a broadcast program), so without prior storage, there can be no reproduction on demand. This problem is particularly troublesome in the event that there are two preferred programs respectively broadcast on different channels concurrently, and a user operates the contemporary television receiver to change the tuned channel from a currently viewed channel broadcasting of one preferred program to the other channel broadcasting the other preferred program, in which case the user is unable to view previous content of the secondly tuned channel.